Scope of Work We will elaborate new classes of de novo proteins that differ radically from natural photosynthetic systems and electron transfer proteins, that will ultimately enable us to decipher the essential engineering criteria important for the efficient conversion of photonic energy into electrochemical potential energy. Ultimately, we aim to establish rules, principles, and quantitative models that describe biological energy conversion by studying designed, well- controlled de novo proteins-systems that permit the logical dissection of structure-function relationships in molecular bioenergetics. Our efforts will include: (i) cofactor design and synthesis, (ii) protein expression, (iii) modern time-resolved spectroscopy, (iv) computational protein design, (v) molecular simulation, (vi) and theoretical analysis of fluctuating charge transport pathways, electronic coupling interactions, and charge migration dynamics.